US4189592A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of 4-methyl-5-[(2-aminoethyl)-thiomethyl]-imidazole dihydrochloride
Assignee: BASF SE
•
Filing: 1979-01-26
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Granted: 1980-02-19
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Expires: 1999-01-26
Abstract
Abstract 4-Methyl-5-[(2-aminoethyl)-thiomethyl]-imidazole dihydrochloride is prepared in a single-step process by thiomethylating 4-methylimidazole. The product is an intermediate for other imidazole derivatives, especially the drug cimetidine.
Inventors
- 👤 Klaus Halbritter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:29
CPC Classifications
C; C07; C07D; C07D233/00; C07D233/54; C07D233/64
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
41 words
A process for the preparation of 4-methyl-5-[(2-aminoethyl)-thiomethyl]-imidazole dihydrochloride, wherein 4-methylimidazole, in excess aqueous concentrated hydrochloric acid, is reacted with cysteamine and formaldehyde or a formaldehyde oligomer, or with thiazolidine or bis-(N-thiazolidinyl)-methane, in a closed system, at from 110° to 170° C.
Claim 2
Dependent Claim
41 words
A process for the preparation of 4-methyl-5-[(2-aminoethyl)-thiomethyl]-imidazole dihydrochloride, wherein 4-methylimidazole, in excess aqueous concentrated hydrochloric acid, is reacted with cysteamine and formaldehyde or a formaldehyde oligomer, or with thiazolidine or bis-(N-thiazolidinyl)-methane, in a closed system, at from 110° to 170° C.
Claim 3
Dependent Claim
20 words
A process as claimed in claim 1, wherein 4-methyl-imidazole, cysteamine and formaldehyde are reacted in the molar ratio of 0.9-1.1:0.9-1.1:0.9-1.4.
References Cited (Backward Citations)
DE2211454A1
Cited
GB1338169A
Cited
US3950333A
Cited
US4053473A
Cited
US4063023A
Cited
US4122277A
Cited
US4112234A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-02-18 | 1983-08-20 | 1984-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-18 | 1987-08-20 | 1988-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-18 | 1991-08-20 | 1992-02-19 | $7700.00 | Window Closed / Lapsed |